Here is a question you never really want to have to ask or look up: Will my pet be OK if it drinks RV antifreeze? The thought is scary as pets shouldn’t really drink anything but water.
Thankfully for your furry partner, they should be OK after drinking some RV antifreeze, but you might not be out of the woods yet.

RV antifreeze is a unique product that is actually OK to ingest in small quantities, but that doesn’t necessarily make it completely safe for pets to ingest.
What is RV antifreeze?
The words “RV antifreeze” might conjure up an image of antifreeze or coolant for a vehicle. These are actually not the same thing. Vehicle antifreeze has ingredients in it called Ethylene Glycol and Methanol, and they are dangerous for consumption whether animal or human. These substances are meant to keep your vehicle’s engine running at a stable temperature in both cold and heat.
Thankfully, we are talking bout a different product in RV antifreeze. RV antifreeze is added to an RV septic system and water system to keep water from freezing in the pipes in cold weather. If you are in an especially cold climate, RV antifreeze can help keep your pipes from bursting as a result of the pressure of expanding ice buildup.
RV antifreeze also often carries the label “Safe for septic” or “Safe for people.” And the label is correct, in a way. When added to the water in your RV, RV antifreeze is diluted enough to make it safe to drink.
What’s in RV antifreeze?
The ingredient we worry a bit about is propylene glycol. You’ll notice that we didn’t list it above with the especially dangerous ingredients for regular vehicle antifreeze.
Is propylene glycol safe for animals?
Just like with humans, the answer is a safe, “It depends.” Yes, propylene glycol and RV antifreeze can be consumed in small amounts, hopefully by accident instead of on purpose. However, especially in dogs, the amount really matters.
A small 1 to 10 pound dog like a Chihuahua can be in trouble when ingesting about 4 milliliters of RV antifreeze. A boston terrier sized animal weighing over 10 pounds could handle 44 ML. As dogs get larger by weight, they can handle more and more.

The threshold for cats varies even more – there isn’t an established one. It just isn’t really safe for them. You should get help from a vet regardless of how much a cat consumes. Your cat could ingest a fatal amount simply by licking it’s paws after accidentally walking through a puddle of antifreeze.
The larger issue with cats is that their nervous system is built differently and they are a smaller animal less able to absorb the impact of chemicals.
Note that 4 ML is a very small amount, like less than a tablespoon.
What are signs of RV antifreeze toxicity in animals?
Pets who ingest too much RV antifreeze can have a few problems:
- Depression
- Weakness
- Involuntary muscle movements, like twitching
- Increased thirst
- Increased urination
In worst case scenarios, they can have a drop in blood pressure or heart problems.
What can I do to prevent my pets from drinking it?
The first and most obvious answer is to store your RV antifreeze in a place where pets and kids can’t get to it. In a locked compartment is preferred.

One challenge with RV antifreeze is that the very substance in propylene glycol smells sweet. If you’ve ever left cookies, peanut butter, or a dessert on the counter, you know your dog’s powerful nose sniffed it and pursued it. In other words, be sure to keep the lid on your RV antifreeze when not in immediate use! Thankfully, most antifreeze manufacturers now add a bitter agent to their antifreeze to keep pets from wanting it – we would suggest smelling your antifreeze before use to see if your manufacturer is on this agreement.
There is also a chance that smaller dogs and cats can be harmed simply by licking RV antifreeze off the ground or inside the RV. The simple solution here is to clean up the area in which you are pouring antifreeze immediately after you pour it. It’s easy to spill a little bit – just be sure the ground around is completely dry before moving on.
It’s also a good idea to keep pets out of the room or area when you are pouring RV antifreeze. They have no idea they could have a big problem if they drink it.
What should I do if my pet drinks it?
Noting that we did establish what are generally safe guidelines for the amount of RV antifreeze pets can drink – you can never be too safe when it actually happens. Call animal poison control or a local vet and they can guide you through the process of going in to get help or finding a way to dilute what your pet drank.
Conclusion
RV antifreeze is not your pet’s friend. The best way to protect your pets from RV antifreeze is to keep it in a locked compartment, don’t leave the bottle open (even if the bitter smell is present), and immediately dry the ground around where you poured RV antifreeze.
If your pet does ingest some, call animal poison control or a veterinarian immediately to get help. While dogs can handle some antifreeze in their system, smaller dogs and cats cannot handle much at all.